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991.
Alexandre Grangeiro Maria Mercedes Escuder Alex Jones Flores Cassanote Rosa Alencar Souza Artur O. Kalichman Valdiléa Veloso Maria Letícia Rodrigues Ikeda Nêmora Tregnago Barcellos Carlos Brites Unai Tupinanbás Noaldo O. Lucena Carlos Lima da Silva Heloisa Ramos Lacerda Beatriz Grinsztejn Euclides Ayres Castilho 《PloS one》2014,9(5)
Background
The HIV-Brazil Cohort Study was established to analyze the effectiveness of combination antiretroviral therapy (cART) and the impact of this treatment on morbidity, quality of life (QOL) and mortality. The study design, patients’ profiles and characteristics of cART initiation between 2003 and 2010 were described.Methodology/Principal Findings
Since 2003, the HIV-Brazil Cohort has been following HIV-infected adults receiving cART at 26 public health care facilities, using routine clinical care data and self-reported QOL questionnaires. When not otherwise available, data are obtained from national information systems. The main outcomes of interest are diseases related or unrelated to HIV; suppression of viral replication; adverse events; virological, clinical and immunological failures; changes in the cART; and mortality. For the 5,061 patients who started cART between 2003 and 2010, the median follow-up time was 4.1 years (IQR 2.2–5.9 years) with an 83.4% retention rate. Patient profiles were characterized by a predominance of men (male/female ratio 1.7∶1), with a mean age of 36.9 years (SD 9.9 years); 55.2% had been infected with HIV via heterosexual contact. The majority of patients (53.4%) initiated cART with a CD4+ T-cell count ≤200 cells/mm3. The medications most often used in the various treatment regimens were efavirenz (59.7%) and lopinavir/ritonavir (18.2%). The proportion of individuals achieving viral suppression within the first 12 months of cART use was 77.4% (95% CI 76.1–78.6). Nearly half (45.4%) of the patients presented HIV-related clinical manifestations after starting cART, and the AIDS mortality rate was 13.9 per 1,000 person-years.Conclusions/Significance
Results from cART use in the daily practice of health services remain relatively unknown in low- and middle-income countries, and studies with the characteristics of the HIV-Brazil Cohort contribute to minimizing these shortcomings, given its scope and patient profile, which is similar to that of the AIDS epidemic in the country. 相似文献992.
Luiza O. Perucci Karina B. Gomes Letícia G. Freitas Lara C. Godoi Patrícia N. Alpoim Melina B. Pinheiro Aline S. Miranda Ant?nio L. Teixeira Luci M. Dusse Lirlandia P. Sousa 《PloS one》2014,9(5)
Background
Despite intensive research, the etiopathogenesis of preeclampsia (PE) remains uncertain. Inflammatory and angiogenic factors are thought to play considerable roles in this disease. The objective of this study was to investigate the association between soluble endoglin (sEng), transforming growth factor beta-1 (TGF-β1) and tumor necrosis factor alpha soluble receptors (sTNF-Rs) and the clinical manifestations of PE.Methods
Plasma levels of sEng, TGF-β1 and sTNF-Rs were determined by ELISA in 23 non-pregnant, 21 normotensive pregnant and 43 PE women. PE women were stratified into subgroups according to the severity [mild (n = 12) and severe (n = 31)] and onset-time of the disease [early (n = 19) and late (n = 24)].Results
Pregnancy was associated with higher levels of sEng, sTNF-R1 and sTNF-R2 than the non-pregnant state. Moreover, PE women had higher levels of sEng and sTNF-R1 than normotensive pregnant women. No difference was found in TGF-β1 levels, comparing the three study groups. Late PE had higher levels of sTNF-R1 and sTNF-R2 than early PE. No significant differences were found in sEng and TGF-β1 comparing early and late PE. sEng levels were higher in severe PE than in mild PE and no difference was found for TGF-β1, sTNF-R1 and sTNF-R2 levels. There was a positive correlation among sEng, TNF-R1 and sTNF-2 levels. Logistic regression analysis revealed that primiparity and sEng levels are independently associated with the development of PE. Furthermore, sEng levels are independently associated with the disease severity.Conclusions
These results suggest that pregnancy is a condition associated with higher levels of anti-angiogenic and pro-inflammatory factors than the non-pregnant state and that PE is associated with an imbalance of these factors in the maternal circulation. 相似文献993.
Alfredo Sahagún-Ruiz Adriana Patricia Granados Martinez Leandro Carvalho Dantas Breda Tatiana Rodrigues Fraga Mónica Marcela Castiblanco Valencia Angela Silva Barbosa Lourdes Isaac 《PloS one》2014,9(10)
Pasteurella pneumotropica is an opportunist Gram negative bacterium responsible for rodent pasteurellosis that affects upper respiratory, reproductive and digestive tracts of mammals. In animal care facilities the presence of P. pneumotropica causes severe to lethal infection in immunodeficient mice, being also a potential source for human contamination. Indeed, occupational exposure is one of the main causes of human infection by P. pneumotropica. The clinical presentation of the disease includes subcutaneous abscesses, respiratory tract colonization and systemic infections. Given the ability of P. pneumotropica to fully disseminate in the organism, it is quite relevant to study the role of the complement system to control the infection as well as the possible evasion mechanisms involved in bacterial survival. Here, we show for the first time that P. pneumotropica is able to survive the bactericidal activity of the human complement system. We observed that host regulatory complement C4BP and Factor H bind to the surface of P. pneumotropica, controlling the activation pathways regulating the formation and maintenance of C3-convertases. These results show that P. pneumotropica has evolved mechanisms to evade the human complement system that may increase the efficiency by which this pathogen is able to gain access to and colonize inner tissues where it may cause severe infections. 相似文献
994.
Aline Lima Leite Janete Gualiume Vaz Madureira Lobo Heloísa Aparecida Barbosa da Silva Pereira Mileni Silva Fernandes Tatiani Martini Fernanda Zucki Dóris Hissako Sumida Alfredo Rigalli Marília Afonso Rabelo Buzalaf 《PloS one》2014,9(9)
Administration of high doses of fluoride (F) can alter glucose homeostasis and lead to insulin resistance (IR). This study determined the profile of protein expression in the gastrocnemius muscle of rats with streptozotocin-induced diabetes that were chronically exposed to F. Male Wistar rats (60 days old) were randomly distributed into two groups of 18 animals. In one group, diabetes was induced through the administration of streptozotocin. Each group (D-diabetic and ND-non-diabetic) was further divided into 3 subgroups each of which was exposed to a different F concentration via drinking water (0 ppm, 10 ppm or 50 ppm F, as NaF). After 22 days of treatment, the gastrocnemius muscle was collected and submitted to proteomic analysis (2D-PAGE followed by LC-MS/MS). Protein functions were classified by the GO biological process (ClueGO v2.0.7+Clupedia v1.0.8) and protein-protein interaction networks were constructed (PSICQUIC, Cytoscape). Quantitative intensity analysis of the proteomic data revealed differential expression of 75 spots for ND0 vs. D0, 76 for ND10 vs.D10, 58 spots for ND50 vs. D50, 52 spots for D0 vs. D10 and 38 spots for D0 vs. D50. The GO annotations with the most significant terms in the comparisons of ND0 vs. D0, ND10 vs. D10, ND50 vs. D50, D0 vs. D10 and D0 vs. D50, were muscle contraction, carbohydrate catabolic processes, generation of precursor metabolites and energy, NAD metabolic processes and gluconeogenesis, respectively. Analysis of subnetworks revealed that, in all comparisons, proteins with fold changes interacted with GLUT4. GLUT4 interacting proteins, such as MDH and the stress proteins HSPB8 and GRP78, exhibited decreased expression when D animals were exposed to F. The presence of the two stress proteins indicates an increase in IR, which might worsen diabetes. Future studies should evaluate whether diabetic animals treated with F have increased IR, as well as which molecular mechanisms are involved. 相似文献
995.
Jansen de Araujo Severino M. de Azevedo Júnior Nicolas Gaidet Renata F. Hurtado David Walker Luciano M. Thomazelli Tatiana Ometto Marina M. M. Seixas Roberta Rodrigues Daniele B. Galindo Adriana C. S. da Silva Arlinéa M. M. Rodrigues Leonardo L. Bomfim Marcelo A. Mota Maria E. Larrazábal Joaquim O. Branco Patricia Serafini Isaac S. Neto John Franks Richard J. Webby Robert G. Webster Edison L. Durigon 《PloS one》2014,9(10)
Aquatic birds are the natural reservoir for avian influenza viruses (AIV). Habitats in Brazil provide stopover and wintering sites for water birds that migrate between North and South America. The current study was conducted to elucidate the possibility of the transport of influenza A viruses by birds that migrate annually between the Northern and Southern Hemispheres. In total, 556 orotracheal/cloacal swab samples were collected for influenza A virus screening using real-time RT-PCR (rRT-PCR). The influenza A virus-positive samples were subjected to viral isolation. Four samples were positive for the influenza A matrix gene by rRT-PCR. From these samples, three viruses were isolated, sequenced and characterized. All positive samples originated from a single bird species, the ruddy turnstone (Arenaria interpres), that was caught in the Amazon region at Caeté Bay, Northeast Pará, at Ilha de Canelas. To our knowledge, this is the first isolation of H11N9 in the ruddy turnstone in South America. 相似文献
996.
Vitor C. Pacheco da Silva Aline Bertin Aurélie Blin Jean-Fran?ois Germain Daniel Bernardi Guylène Rignol Marcos Botton Thibaut Malausa 《PloS one》2014,9(7)
Mealybugs (Hemiptera: Pseudococcidae) are pests constraining the international trade of Brazilian table grapes. They damage grapes by transmitting viruses and toxins, causing defoliation, chlorosis, and vigor losses and favoring the development of sooty mold. Difficulties in mealybug identification remain an obstacle to the adequate management of these pests. In this study, our primary aim was to identify the principal mealybug species infesting the major table grape-producing regions in Brazil, by morphological and molecular characterization. Our secondary aim was to develop a rapid identification kit based on species-specific Polymerase Chain Reactions, to facilitate the routine identification of the most common pest species. We surveyed 40 sites infested with mealybugs and identified 17 species: Dysmicoccus brevipes (Cockerell), Dysmicoccus sylvarum Williams and Granara de Willink, Dysmicoccus texensis (Tinsley), Ferrisia cristinae Kaydan and Gullan, Ferrisia meridionalis Williams, Ferrisia terani Williams and Granara de Willink, Phenacoccus baccharidis Williams, Phenacoccus parvus Morrison, Phenacoccus solenopsis Tinsley, Planococcus citri (Risso), Pseudococcus viburni (Signoret), Pseudococcus cryptus Hempel, four taxa closely related each of to Pseudococcus viburni, Pseudococcus sociabilis Hambleton, Pseudococcus maritimus (Ehrhorn) and Pseudococcus meridionalis Prado, and one specimen from the genus Pseudococcus Westwood. The PCR method developed effectively identified five mealybug species of economic interest on grape in Brazil: D. brevipes, Pl. citri, Ps. viburni, Ph. solenopsis and Planococcus ficus (Signoret). Nevertheless, it is not possible to assure that this procedure is reliable for taxa that have not been sampled already and might be very closely related to the target species. 相似文献
997.
Aline S. Bossa Vera M. C. Salemi Susan P. Ribeiro Daniela S. Rosa Ludmila Rodrigues Pinto Ferreira Suzete C. Ferreira Anna Shoko Nishiya Charles Mady Jorge Kalil Edecio Cunha-Neto 《PloS one》2014,9(10)
Background
The participation of immune/inflammatory mechanisms in the pathogenesis of tropical endomyocardial fibrosis (EMF) has been suggested by the finding of early blood and myocardial eosinophilia. However, the inflammatory activation status of late-stage EMF patients is still unknown.Methodology/Principal findings
We evaluated pro- and anti-inflammatory cytokine levels in plasma samples from late stage EMF patients. Cytokine levels of Tumor Necrosis Factor (TNF)-α, Interferon (IFN)-γ, Interleukin (IL)-2, IL-4, IL-6, and IL-10 were assayed in plasma samples from 27 EMF patients and compared with those of healthy control subjects. All EMF patients displayed detectable plasma levels of at least one of the cytokines tested. We found that TNF-α, IL-6, IL-4, and IL-10 were each detected in at least 74% of tested sera, and plasma levels of IL-10, IL-4, and TNF-α were significantly higher than those of controls. Plasma levels of such cytokines positively correlated with each other.Conclusions/Significance
The mixed pro- and anti-inflammatory/Th2circulating cytokine profile in EMF is consistent with the presence of a persistent inflammatory stimulus. On the other hand, the detection of increased levels of TNF-α may be secondary to the cardiovascular involvement observed in these patients, whereas IL-4 and IL-10 may have been upregulated as a homeostatic mechanism to buffer both production and deleterious cardiovascular effects of pro-inflammatory cytokines. Further studies might establish whether these findings play a role in disease pathogenesis. 相似文献998.
Ricardo Q. Gurgel Alberto De Juan Alvarez Alda Rodrigues Robergson R. Ribeiro Sílvio S. Dolabella Natanael L. Da Mota Victor S. Santos Miren Iturriza-Gomara Nigel A. Cunliffe Luis E. Cuevas 《PloS one》2014,9(10)
Background and Aims
Rotavirus causes severe diarrhoea and Brazil introduced the Rotarix G1P[8] vaccine in 2006. We aimed to describe changes in rotavirus incidence and diarrhoea epidemiology before and after vaccine introduction.Methods
Design: (i) hospital-based survey of children with diarrhoea (2006–2012); (ii) diarrhea-mortality and hospitalization surveillance (1999–2012).Setting
(i) Aracaju and (ii) state and national level.Results
1841 children were enrolled and 231 (12.5%) had rotavirus. Rotavirus was less frequent from January-June than from July-December (9.4% versus 20.9%, p<0.01), but the seasonal variation was less defined after 2009. Very few rotavirus cases (8–3.9%) were detected in 2011, with an increase in 2012 (13–18.5%). In 2006, unvaccinated children were more likely to have rotavirus, but thereafter unvaccinated and vaccinated children had equally low incidence. Older children and those with rotavirus were more likely to have severe diarrhea episodes. The most frequent genotype from 2006 to 2010 was G2P[4]; except in 2009, when most cases were G1P[8]. Very few G2P[4] were detected from 2011 and 50% cases in 2012 were G8P[4]. Diarrhoea-hospitalizations decreased nationally from 89,934 (2003) to 53,705 (2012; 40.3% reduction) and in the state from 1729 to 748 (56.7% reduction). Diarrhoea-deaths decreased nationally from 4368 in 1999 to 697 in 2012 (84% reduction, p<0.001) and in the state from 132 to 18 (86% reduction). These changes were much larger after vaccine introduction.Conclusions
The vaccine was associated with substantial reductions in rotavirus incidence and diarrhoea-hospitalizations and deaths. The G2P[4] genotype predominance disappeared over time and may be replaced by other heterotypic genotypes. 相似文献999.
Aline Rideau Batista Novais Nadine Crouzin Mélanie Cavalier Mathilde Boubal Janique Guiramand Catherine Cohen-Solal Marie-Céleste de Jesus Ferreira Gilles Cambonie Michel Vignes Gérard Barbanel 《PloS one》2014,9(9)
Maternal inflammation during pregnancy is associated with the later development of cognitive and behavioral impairment in the offspring, reminiscent of the traits of schizophrenia or autism spectrum disorders. Hippocampal long-term potentiation and long-term depression of glutamatergic synapses are respectively involved in memory formation and consolidation. In male rats, maternal inflammation with lipopolysaccharide (LPS) led to a premature loss of long-term depression, occurring between 12 and 25 postnatal days instead of after the first postnatal month, and aberrant occurrence of long-term potentiation. We hypothesized this would be related to GABAergic system impairment. Sprague Dawley rats received either LPS or isotonic saline ip on gestational day 19. Male offspring''s hippocampus was studied between 12 and 25 postnatal days. Morphological and functional analyses demonstrated that prenatal LPS triggered a deficit of hippocampal GABAergic interneurons, associated with presynaptic GABAergic transmission deficiency in male offspring. Increasing ambient GABA by impairing GABA reuptake with tiagabine did not interact with the low frequency-induced long-term depression in control animals but fully prevented its impairment in male offspring of LPS-challenged dams. Tiagabine furthermore prevented the aberrant occurrence of paired-pulse triggered long-term potentiation in these rats. Deficiency in GABA seems to be central to the dysregulation of synaptic plasticity observed in juvenile in utero LPS-challenged rats. Modulating GABAergic tone may be a possible therapeutic strategy at this developmental stage. 相似文献
1000.
Camila Nassif Aline Regina Gomes Gustavo H. C. Peixoto Mauro Heleno Chagas Danusa Dias Soares Emerson Silami-Garcia Eric J. Drinkwater Jack Cannon Frank E. Marino 《PloS one》2014,9(8)
This study evaluated double blind ingestions of placebo (PLA) versus 6% carbohydrate (CHO) either as capsules (c) or beverage (b) during 60 km self-paced cycling in the heat (32°C and 50% relative humidity). Ten well-trained males (mean ± SD: 26±3 years; 64.5±7.7 kg and 70.7±8.8 ml.kg−1.min−1 maximal oxygen consumption) completed four separate 60 km time trials (TT) punctuated by 1 km sprints (14, 29, 44, 59 km) whilst ingesting either PLAb or PLAc or CHOb or CHOc. The TT was not different among treatments (PLAb 130.2±11.2 min, CHOb 140.5±18.1 min, PLAc 143.1±29.2 min, CHOc 137.3±20.1 min; P>0.05). Effect size (Cohen’s d) for time was only moderate when comparing CHOb – PLAb (d = 0.68) and PLAb – PLAc (d = 0.57) whereas all other ES were ‘trivial’ to ‘small’. Mean speed throughout the trial was significantly higher for PLAb only (P<0.05). Power output was only different (P<0.05) between the sprints and low intensity efforts within and across conditions. Core and mean skin temperatures were similar among trials. We conclude that CHO ingestion is of little or no benefit as a beverage compared with placebo during 60 km TT in the heat. 相似文献